Multiple circulation boiler



Sept. 8, 1931. H. J. s. M KAY 1,822,228

MULTIPLE CIRCULATION BOILER I I Filed Oct. 12, 1925' INVENTOR BY I WIBJMZ",

, A TTORNE ks Patented Sept. 8, 1931 UNITED STATES PATENT OFFICE HENRYJOHN SUTHERLAND MAOKAY, OF LONDON, ENGLAND, ASSIGNOR TO THE BAIB- COCK &WILCOX COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEYMULTIPLE CIRCULATION BOILER Application filed October 12, 1925, SerialNo. 61,875, and. in Great Britain December 15, 1924.

This invention relates to a boiler in which a plurality of watercirculation systems or circuits is used and in which furnace gases ofdiflerent temperatures contact with the respective systems, and willbest be understood from the description in connection with theaccompanying drawings, in which Fig. 1 is a longitudinal section throughthe boiler and Fig. 2 is an elongated longitudinal section through therear steam and water drum.

This invention is especially adapted to steam generators of the drum andwater tube type, including top and bottom drums so disposed andconnected as to provide separate and distinct circuits between the topand bottom drums, and a common circuit between the top drums.Heretofore, in steam generators of this type, the feed inlet has beenlocated in one of the bottom or mud drums, or the feed water has beenintroduced directly into one of the top drums. By introducing the feedwater inthis manner, troubles have been caused by the corrosive actionof the gases contained in the feed water. By the present invention, thefeed water is supplied to a pan or trough located in the steam space ofthe rear steam and water drum, and this trough is connected withdowntake tubes of one of the circuits, extending from the top drum toone of the lower mud or sediment drums, in such a manner that the airand dissolved gases are liberated from the feed water before it or as itpasses into the circulation, and the feed water so freed from air andgases is led directly to the bottom drum of the circuit which iscontacted by the cooler gases from which it passes through the frontbank of tubes of this circuit to the front top drum, thence through thecommon steam and circulating tubes to the rear'top drum, and v thenceinto a circuit contacted by hotter gases. In the illustrative embodimentshown in the drawings, the inner circuit is the one that is subjected tocooler gases than the outer circuit and by depositing the mud andsediment in the drum of the inner circuit, the outer circuit which issubjected to the hotter gases is kept free from mud or sediment and tubetroubles are thereby avoided.

In the illustrative embodiment shown in the drawings, a mechanicalstoker 10 of the chain grate type is installed in the usual manner atthe lower portion of the boiler setting, the front, rear and side wallsof which are shown at 11, 12 and13, respectively. The front steam andwater drum 14 and the rear steam and water ,drum 15, are connected, asusual, by steam and water circulating tubes 16. Two mud or sedimentdrums 17 and 18 are disposed in a lower'so plane, the drum 17 beingslightly above drum 18, and these drums are rovided with valved blow-offpipes 19. n auxiliary drum 20 may be located at the rear of the grate10, and may be connected by means 5 of a tube or tubes 21 to the muddrum 18. r

A bank of downtake tubes 23 connects the steam and water drum 15 to themud drum 17. A bank' of downtake tubes 24 connects the drum 15 to themud drum 18, a bank of uptake tubes 25 connects the drum 17 to the steamand water drum 14, and a bank of uptake tubes 26 connects the drum 18 tothe drum 14. A pipe 27 leads from the steam space of the steam andwater'drum 15 to the superheater 28. Battles 30, 31, 32 and 33 areprovided, in the usual manner, to direct the hot products of combustionacross the water tubes and into the outlet 34 for the gases.

A vertically disposed dash plate 36 with perforations 31 near its upperedge is placed longitudinally within the drum 15 and ex- I tends fromnear the top wall thereof to a'distance slightly below the normal waterlevel in this drum, for the purpose of facilitating the separation ofthe steam and water which enters this drum from the circulating tubes16. A dry pipe 38 connected to pipe or pipes 27 is located on the otherside of the dash plates 36 from the tubes 16, and extends 16nanddissolved gases are liberated, and then the feed water flows downwardlythrough the tubes 41 into tubes 23 and then into the mud drum 1'2,thence through the tubes 25 to the front steam and water drum 14;,thence through the common steam and water circulation tubes 16 to therear steam and water drum 15, from whence a portion passes downwardlythrough the downtake tubes 24 into the lower muddrum 18, through thetubes 26 into the front steam and water drum 14, and through the tubes16 to the drum 15, the other portion passing downwardly through downtaketubes 23 into the upper mud drum 17, through the tubes 25 to the drum14. The steam from the tubes 16 flows through-the perforations 37 in thebaffle 86, and then through the pipes 38 and 27 to the superheater 33.

A single drum with a partition therein may be used instead of the twoillustrated drums 17 and 18, the banks of tubes leading to and from theseparate portions of the drum being contacted with gases of differenttemperatures so as to constitute different, circuits into one of whichthe feed water may be introduced after it has been heated as above de"scribed.

I claim 1. A water tube boiler comprising front and rear steam and waterdrums, steam and water tubes connecting said drums, at least two lowerdrums one disposed above the other, sets of uptake tubes and downtaketubes connecting said upper and lower drums, said sets of uptake tubesand downtake tubes being each divided into at least two groups, each ofsaid groups being connected to one of said lower drums, thus affording'separate inner and outer circuits, and means for feeding water into thesteam space of the rear drum and thence directly into dow take tubes ofsaid inner circuit.

2. A water tube boiler comprising front and rear steam and water drums,steam and water tubes connecting said drums. at least two lower drumsone disposed above the other, sets of uptake tubes and downtake tubesconnecting said upper and lower drums. said sets of u take tubes anddowntake tubes being each divided into at least two groups, each of saidgroups being connected to one of said lower drums, thus affordingseparate inner and outer circuits, and a feed trough within the steamspace of the rear steam and asaaeee water drum and connections betweensuch feed trough and selected downtake tubes of the said inner circuit.

3. In a boiler, a steam and water drum having a receptacle in the steamspace there of, means for discharging feed water into said receptacle,steam tubes arranged to discharge steam into the steam space of the drumand over the water in said receptacle, and means between said receptacleand the ends of said tubes to separate the steam from the entrainedwater.

4.. In a boiler, a steam and water drum having a receptacle in the steamspace thereof, means for discharging feed water into said receptacle,steam tubes arranged to discharge steam into the steam space of the drumand over the water in said receptacle, means be tween said receptacleand the ends of said tubes to separate the steam from the entrainedwater, and a dry pipe disposed in the steam space of the drum above thereceptacle and having a connection to the steam outlet of the drum. I

5. In a boiler, a steam and water drum having a steam inlet and outlet,a receptacle disposed between the inlet and the outlet, means forintroducing feed water into said receptacle whereby the steam passingfrom the inlet to the outlet will come into contact with the water inthe receptacle, and means between the inlet and outlet adapted to directthe steam irom the inlet into contact with the water in the receptacleon its way to the outlet.

6. In a boiler, a steam and water drum having a steam inlet and outlet,a receptacle disposed between the inlet and the outlet, means forintroducing feed water into said receptacle whereby the steam passingfrom the inlet to the outlet will come into contact with the water inthe receptacle, and a plate disposed between the receptacle and theinlet with its lower edge beneath the normal water level in the drum,said plate having a plurality of apertures through which the steam maypass on its way from the inlet to the outlet.

7. In a boiler, a plurality of circulation systerns, a steam and waterdrum common to all said systems and having a pan in the steam spacethereof. means for discharging feed water into said pan, and aconnection from said pan directly into one of said circulation systems,said connection segregating the feed water from the boiler water in theother systerns.

8. In a boiler, a steam and water drum having a pan disposed in thesteam space thereof, means for discharging feed water into said pan,water tubes leading from the water space of said drum, and connectionsleading from the pan directly to said tubes and segregating the waterpassing through the connections from the water in the drum.

9. In a boiler, water dirt".

having a pan disposed in the steam space thereof, a row of tubesextending lengthwise of the drum and connected to the water spacethereof, means for passing hot gases in contact with said row, a row ofconnections leading from said pan directly to tubes in said row, andmeans for supplying feed water to said pan.

In testimony whereof I have signed my name to this specification.

HENRY JOHN SUTHERLAND MACKAY.

